The MerVal index .MERV of the 25 leading stocks rose 0.47 percent at 2,140.31 points. The index is up 2.4 percent since the start of the year.

"The closing of positions as options expired sparked upward movement in the MerVal during the last hour of the session, which corresponded to a better external context," said Marcelo Paccione, analyst at ConsultCapital consultancy.

"The gains were supported by shares linked to the options contracts, like Grupo Financiero Galicia, Pampa Holding and Molinos," Paccione said.